<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <script>
      const dictionary = Object.create(null);
      dictionary.apple = 'Apple';
      dictionary.__proto__ = 'test';
      // dictionary.total = 100;
      Object.defineProperty(dictionary, 'toString', {
        value: function () {
          return Object.values(this).join(',');
        },
        enumerable: false,
      });
      console.log(String(dictionary));

      for (let key in dictionary) {
        console.log(key);
      }
    </script>
  </body>
</html>
